An electric power for machining is supplied to an electrode wire in an electrospark machining area of a wire-cut electrical discharge machine. Namely, a discharge voltage is applied between the electrode wire and a workpiece through an electric power supply member, and thereby an electrospark is formed at a small gap therebetween in an electrospark machining area and machining is carried out. However, an electric charge remains in a used wire that has passed through the electrospark machining area and reached a used wire collection section, because of the electric power supply to the electrode wire. Therefore, in the prior art, a cover member made of an electrical insulating material such as a plastic material, is fitted over a path of the electrode wire to be collected in the wire collection section, to protect a worker from the affects of an electric shock caused by touching the electrode wire. Specifically, when the used electrode wire reaches the used wire collection section area, it is always electrically charged, because an automatic connection of wires is immediately made when an electrode wire is cut in the electrospark machining area in the latest wire-cut electrical discharge machine provided with an automatic wire connection device. In consequence, a problem arises of safety in that the wire can be touched before the same is completely collected in the wire collection section. Therefore, the cover member is fitted to prevent accidents due to an electric shock.
This safety is secured by the cover member as mentioned above when the electrode wire is normally collected while the electrospark machining is continuously carried out by an automatic connection of wires, even though an electrode wire is cut in the above-mentioned wire-cut electrical discharge machine provided with an automatic wire connection device. Nevertheless, if the problem of an over-accumulation of used electrode wire in the wire collection section occurs, a disturbance of the running of the electrode wire to the wire collection section after having passed through the electrospark machining area occurs, and the electrode wire will touch a conductive part or the machine body near the path of the running electrode wire, and consequently, an electric charge will leak through the machine portion and outside the area provided with a cover member, to cause an accident due to an electric shock.